Quarter Wave / T-Line tutorial-UPDATED

[LSN2meBoom916]

ok SWEET!

I knew I passed 6th grade for a reason other than kickball skillz and cutting along the lines.

But I still dont get where that 160in^2 on the 1st page came from?

Not important other than I am a curious mofo and would like to know. Maybe it's from his "iso-bandpass-T-line" magic calculations.

[vad333]

wrong!!!!!

you need to measure from mid of surround to mid. of surround.

12" sub dia =9.5" aprox. sd=78^in .case closed

[Forevrbumpn]

Got the math down quick I see LSN, your right on the nose.  And, SD, is Cone area, so if you have #'s for SD, use them instead of measuring the cone, the sd will be more accurate. Using SD/Cone area is only a alternatice, there are many other ways to determine port area, tapering, ect. But to keep this thread as simple as possible, just try cone area, x's Fs- or boost gain as the quarter wave length

[LSN2meBoom916]

wrong!!!!!

you need to measure from mid of surround to mid. of surround.

12" sub dia =9.5" aprox. sd=78^in .case closed

WHOA dude! Why do you sound/seem upset?

I am using a 10in sub, not a 12 so i dunno what ur comment is about either.

Got the math down quick I see LSN, your right on the nose.  And, SD, is Cone area, so if you have #'s for SD, use them instead of measuring the cone, the sd will be more accurate. Using SD/Cone area is only a alternatice, there are many other ways to determine port area, tapering, ect. But to keep this thread as simple as possible, just try cone area, x's Fs- or boost gain as the quarter wave length

Yessir.

So i think you KINDA answered my Q just there but I wanna make sure b4 I get to buildin it.

You said:..."try cone area, x's Fs..." as in to get the port area right?

So in my case it'd be 50in^2 (sd of my 10in HCCA sub) TIMES 42(hz, my Fs)...

So 50x42=2100! No way it needs 2100in^2 of port.

This is what confused me. I think 50in^2 sounds more like it.

Sorry for the confusion just tryin to clarify on this. I LOVE box design and this one looks like DOOZY. :w00t:

[stratusrt01]

After you do a couple designs, it gets easier.  The hard part is getting them to fit in the dimensions you have to work with, unless you have a van or large SUV.

[LSN2meBoom916]

So the port area SHOULD be = to Sd then right?

Mine would be 50in^2 per 10in sub??

Me thinks. :nerd:

[stratusrt01]

that's the way I understood it, and built it, and it worked for me

[LSN2meBoom916]

Ok gracias muchisimo.

Time to try out the new brad nailer/compressor  :w00t:

i shall post accomplishments/failures.

[Forevrbumpn]

Got the math down quick I see LSN, your right on the nose.  And, SD, is Cone area, so if you have #'s for SD, use them instead of measuring the cone, the sd will be more accurate. Using SD/Cone area is only a alternatice, there are many other ways to determine port area, tapering, ect. But to keep this thread as simple as possible, just try cone area, x's Fs- or boost gain as the quarter wave length

Wow, I wrote that a little fast, and didnt proof read it before sending, lol Dohh!!

I dont know what I was getting at, but yeah, SD x's Fs, I have no idea where my head was!!! Think I was just saying, For a begginer, just use SD as a reference for port area, and Fs or Boost as the line length, and work from there- Then later, you can learn tapering, and horn design/theory

[LSN2meBoom916]

ok sweet that's what I thought and Stratus Helped a bit on that one clearin it up.

I knew the 2100# was way off.

From the sounds of it i'mma have new compressor/brad nailer/staple gun setup in day or 2 and I just might hit this thing up if no one tries to buy those orion 10's out from under me.If so, oh well I hvae about 20 subs to play with so it shall go down in some form and I'll keep yall posted.

Thanx again for the ideas.